Inspection light



G. ELLIS INSPECTION LIGHT Dec. 13, 1949 Original Filed Jan. 7, I943INVENTOR BY ATTORNE S Patented Dec. 13, 1949 INSPECTION LIGHT GreerEllis, Chicago, Ill., asslgnor, by mesne assignments, to Joseph L.Switzer and Robert C.

Switzer Original application January 7, 1943, Serial No. 471,545.Divided and this application October 21, 1944, Serial No. 559,735

2 Claims. (Cl. 240-41) 1 This invention'relates to inspection lights andmountings therefor. More particularly, this invention relates to anultraviolet inspection light and a mounting which permits the convenientuse of the light either as a fixed and focused light or as a portablespot-light. This application is a division of my copending applicationfor Inspection light, filed January 7, 1943, Serial 471,545, now PatentNo. 2,388,474, granted November 6, 1945.

Inspection lights made according to this invention are especially usefulin inspecting articles according to the methods disclosed in U. S.Patents Nos. 2,259,400 and 2,267,999. As these methods are usuallypracticed, articles carrying fluorescent indications of flaws anddefects are inspected under filtered ultraviolet light in inspectionbooths which are substantially closed in order to shut out visiblelight. As may be appreciated, the working conditions in such booths arenot best. The diillculty of ventilating such closed booths makes itdesirable to use as few inspection lights as possible, not only foreconomy in equipment, but also to reduce heat developed by the lights;otherwise, the temperatures in the booths may become unbearable. Thelack of visible light requires that such inspection booths be asuncluttered as possible; otherwise, costly delay and confusion is almostcertain to arise in production inspection.

In certain types of fluorescent inspection, as where both large andsmall objects are examined,

it is desirable to have a fixed light to permit small objects to bepicked up in the hands for examination and a portable spot-light topermit large, heavy objects to be examined. In order to avoid the use oftwo lamps, use of a demountable s ot-light was indicated. Demountablespot-lights available to the prior art, usually mounted by means of aspring or screw clamp,v

were 'very unsatisfactory; two liands were required to mount and demountthe lights if a screw clamp was employed or if the spring clamp wasstrong enough to hold the light rigid; spring clamp lights also tendedto fatigue the operator's hands; remounting the lights was difllcult andconfusing in the absence of visible light; if the clamp was fixed to thelight, as was usually thecase, the clamp tended to become tangled withthe light cord. By far the greatest objection to demountable lights,however, was that entirely too much time was required to refocus thelight after it had been remounted. Table lamps on tion, and alsocluttered up the inspection table. As a result of the foregoingdisadvantages, there was a tendency to use both a fixed light and aportable light, both of which were constantly operated to avoid timelost in waiting for the light to warm up and in waiting for the light tocool down before restarting the light. The disadvantages of using twoconstantly operating lights were less than the disadvantages of thedemountable portable lights known to the prior art.

It is the object of this invention to provide an ultraviolet inspectionlight and mounting therefor which will permit the convenient use of thelight both as a fixed inspection light and as a portable spot-light.More specifically, it is the object of this invention to provide aninspection light which may be instantly, and with one hand, demounted orremounted and which, when remounted, will be automatically and securelyrefocused. It is also an object of this invention to provide aninspection light which may be conveniently manipulated withoutentangling the light cord.

It is a furtherobject of this invention to provide an inspection lightin which the light bulb support will insure that the bulb is in properfocus and, at the same time, protect the bulb from sudden shocks.

Other and still further objects and advantages of my invention will beapparent from the following specification, claims, and drawings, inwhich:

Fig. 1 is an elevation, partly in section and partly diagrammatic, of aninspection light and mounting made according to my invention.

Fig. 2 is a developed plan, partly in section, taken along the line 2--2of Fig. 1.

The embodiment of my inspection light and mounting disclosed in thedrawings employs a universal mounting Ill and a light 30, the mountingIll permitting the light 30 to be aimed or focused at substantially anyspot within the booth in which the unit is employed. The mounting I0 iscomprised of a bracket H, fixed o the wall of the booth, which bracketcarries a bracket 1 arm I! pivotal on a vertical axis. The bracketportable stands were not satisfactory; the lamps were clumsy, requiringtwo hands for manipulaarm l2 may be locked in any position to which itmay be swung by the locking thumb bolt IS, the lower vertical pivot forthe bracket arm. The bracket arm I! terminates in a boss having avertical serrated surface which mates with the similarly serratedsurface of the boss IS on the stud arm It. The mating serrated surfacesof the bosses II and I5 are held in looking engagement by the thumb boltI! which, when the bosses are disengaged, serves as a horizontal pivotpermitting the stud arm I6 to swing in a vertical lane. rical studsleeve i8 in which the stud is received.

The stud 20 comprises a lower cylindrical staff portion 2| and an upper,square, index stafl portion 22, the two staff portions being separatedbya central flange 23. The cylindrical staff portion 2| is preferablyshorter than the stud sleeve I8 and the end of the staff portion 2| istapped to receive the thumb bolt 24, which carries a suitable lockwasher. As is apparent from the drawings, the cylindrical staff portion2| is rotatable in the sleeve i8 and may be locked in any rotatedposition by tightening on the thumbbolt 24 to lock the sleeve betweenthe flange 23 and the lock washer carried by the bolt.

The light comprises an open-ended shell 3|, preferably of a streamlinedshape. Within the apex or closed end of the shell 3|, 9, shortaxially-extending ring fitting 32 is secured. The fitting 32 supports asocket 33 in which a mercury-arc bulb and reflector unit 34 is carried,the bulb unit 34 being provided with a suitable filter 34f to filter outvisible light and pass ultraviolet light emitted by the bulb unit 34.The open end of the shell 3| is covered by a suitably secured, removablehood 35, the forward end of the hood 35 being provided with an opengrille 3G, comprised of one or more suitably supported concentric ringsin this instance. A plurality of axially-extending centering springleaves 31, preferablythree, are secured at one end to the inner wall ofthe hood. For the major portion of their length these centering leaves31 are spaced inwardly of the hood wall and are centered about thelongitudinal axis of the hood and shell, the free ends of the centeringleaves being slightly outwardly flared so that the leaves will engage,and be slightly sprung by, the rim of the bulb unit 34. A plurality ofventilating openings 38 are located adjacent the apex of the shell 3| topermit the passage of cooling currents of air around the bulb unit 34,the open grille 36 and the openings 38 constituting the necessaryentrance and exit for such currents. A lead-in opening 39 is alsoprovided near the apex of the shell 3|.

The shell 3| is supported by a hollow pistolgrip handle 40 secured tothe shell 3| by belts or other suitable means, the handle beingpositioned upon the shell so that the light as a whole will beconveniently balanced when held in the hand. The shell 3| may be spacedfrom the handle 40 by resilient washers 4|, as shown. Although thehandle 40 is largely hollow, the butt of the handle is made solid toprovide walls for a square index socket 42 in which the index staff 22of the stud 20 will be slidably received. A light-cord passage 43 isalso provided through the butt of the handle 4|] forwardly of the indexsocket 42. The back of the handle is preferably extended to serve as aguard over the leadin opening 39.

Electric current for operating the light is obtained from any suitablesource through the auto-transformer 5| and spring reel 52 mounted in oron the wall of the booth. From the spring reel 52, the light-cord 5|) isled up through the passage 43 in the butt of the handle 40, through thelead-in opening 39 in the shell 3| and thence to the socket 33 throughthe ring fitting 32.

To use the above described embodiment of my invention as a fixed light,the light is focused The stud arm l6 terminates in a cylin-,

by means of the universal mounting ill. Focusing is usually accomplishedby swinging the bracket arm |2 in the bracket until the vertical planeof the bracket arm is aligned with the desired point on the inspectiontable. With the thumb bolt loosened, the stud arm I6 is pivoted untilthe lamp is focused on the desired point; the thumb bolts i3 and I1 arethen tightened to lock the mounting in its adjusted positlon. The stud20 is usually locked in the sleeve l8. By loosening the thumb bolt 24,however, it is possible to obtain a sort of vernier adjustment betweenthe fixed angles of adjustment permitted by the serrations of the bossesl4 and I5. By making the stud 20 pivotal in the sleeve l8, it ispossible to swing the mounting l0 close to the wall on which it ismounted. It is also possible to focus the light on a point immediatelybeneath the mounting by swinging the stud arm Ii to a substantiallyvertical position and then reversing the stud 20 in the sleeve l8.

To use my light as a portable spot-light, the handle 40 is grasped andthe light 30 is simply lifted off the stud 20. Such additional lengthsof light-cord as may be required will be paid off by the spring reel 52,which is preferably of the ratchet type so that there will be no pull onthe cord 50 to distract the operator while manipulating the light. Thewell-balanced shell on the pistol-grip handle obviously allows the lightto be easily manipulated with one hand, leaving the operator's otherhand free at all times, even during demounting and remounting. Becausethe cord 50 is led in through the butt of the handle and because thereis no protuberance below the handle in this preferred embodiment. thepossibility of the cord's becoming entangled is reduced to a minimum.Although rough usage of the light is not recommended, the single fitting32, which is slightly resilient, and the resilient centering leaves 3!protect the bulb unit 34 against sudden shocks which might otherwisecrack the electrodes within the bulb. The resilient washers 4| alsoabsorb some physical shocks.

To remount the light, the handle 40 is simply placed on the stud 20 sothat the index staff 22 slides into the index socket 42. Thus, the lightis automatically refocused when remounted. If the spring reel is of theratchet type, a slight pull on the cord 50 will release the pawl andcause the reel to take up excess cord. The capacity of the reel ispreferably such that a slight amount of slack will always be provided topermit the handle 40 to be lifted off the index staff 22. By having thecord lead-in passage 43 forward of the index socket 42, there is notendency for the card 50 to become entangled with the mounting While theforegoing is a description of a preferred embodiment of my invention, itshould be apparent that my invention may be modified by those skilled inthe art. For example, the switch for the lighting circuit is indicatedin the drawings as being located on the line side of the transformer 5|;the type and location of this switch is obviously a matter of choice.For instance, the lighting switch could be a toggle switch locatedforwardly of the pistol-grip handle 40 to be worked by the operator'strigger-finger; such a switch permitting instant control of the lightwould afford no advantage in the embodiment disclosed because mercuryvapor lights require several minutes to warm up. Also, the close slidingfit between the index staff 22 and the index socket 42, as shown,usually provides an amply secure connection between the mounting l0 andthe light to obtain a more secure connection, the indexing staff 22 maybe provided with a spring catch or the handle may be provided with astud-engaging lat-ch. Because the sections of the indexing staff 22 andthe socket 42 are square, it would be possible to remount the light 20so that it would be indexed or from its focused position, although theprobability of such an occurrence would be quite remote in actualpractice; in order to eliminate this remote possibility. the indexingstall and socket may be made with an unbalanced or irregular section,as, for example, by providing a fiat on an otherwise circular section;any non-circular cross-section on a projection slidably received in amating socket will usually suflice, the term non-circular cross-sectionbeing understood to include the cross-section of a plurality of pins,whose total cross-section is non-circular, as well as the crosssectionof a sin le projec ion or stud. Further, the indexing stafl' 22 and/orthesocket 42 may be tapered to aid in r'emounting the light. Thespecific universal mounting I0 is preferred because the several lockingthumb-bolts are readily accessible though not likely to interfere withthe mounting or demounting of the light; obviously. within the scope ofthis invention, other universal mountings may be employed.

While this disclosure has been directed to the use of my light as asource of filtered ultraviolet light, my light may also be used as asource of visible light. It should be apparent. therefore, that myinvention is not limited to the specific use or embodiment disclosed butby the appended claims.

What is claimed is:

1. In a demountabie lighten envelope, a light bulb, a singlecomparatively rigid fitting for supporting said light bulb axiallywithin said en'velope, and comparatively resilient means engaging saidlight bulb oppositely of said fitting and resiliently spacing said bulbfrom said envelope to protect said bulb from physical shocks, a handleconnected to'said envelope to permit the light to be manipulated whendemounted, said handle having an index socket having a non-circularcross-section to index the light when mounted.

2. In a demountable light, the combination as defined in claim 1 inwhich said envelope comprises an open-ended prolate spheroidal shell anda hood covering the open end of said shell, said 1:, fitting beinglocated adjacent the apex of said shell and said resilient means beingsecured to' said hood, and said handle having a light-cord passageadjacent said socket.

GREER ELLIS.

' 7 REFERENCES CITED The following references are of record in the fileof this patent:

25 UNITED STATES PATENTS Number Name Date 446,142 Martin Feb. 10, 1891649,544 Morse May 15, 1900 7 1,097,588 Jackson May 19, 1914 20 1,240,452Hotchkin Sept. 18, 1917 1,313,739 Ryerson Aug. 19, 1919 2,138,070 Tayloret al. Nov. 29, 1938 2,278,545 Gravenstine Apr. 7, 1942 2,285,002 WilsonJune 2, 1942 2,286,934 Sale June 18, 1942 FOREIGN PATENTS Number CountryDate 570,390 Germany o! 1933

